Twin Engine Profile Scale Warbirds from RabidModels.com™

Regarding the GWS motors and props:

GWS 3x2 props are normally supplied with a 1mm-size hole. The shaft on the GWS motor is 1.5mm.

You can force the prop on, but it’s difficult and it’s easy to damage the motor’s bearings. It’s also virtually impossible to remove the prop later, if you ever need to change it.

For best results the propeller’s hole needs to be enlarged very slightly. A 1/16 drill bit is too big. You may use either a #54 or a #53 wire-size bit. We realize that this kind of drill bit may be difficult to find. With experience we have learned that it is very important for the prop to fit correctly. A drill press is the best tool for the job.

Using the #54 bit will result in a very tight fit – if you wiggle the bit slightly, it comes out right. The prop must be a tight fit. The #53 bit is slightly too big, and if you use it the propeller may not be tight enough and can come off. (See disclaimer below).

Here is a chart showing how a #54 bit compares:

0.0394 inches = 1.0mm 0.0550 inches = #54 bit 0.0551 inches = 1.4mm 0.0591 inches = 1.5mm 0.0595 inches = #53 bit (too big) 0.0625 inches = 1/16 inch bit (too big)

DISCLAIMER: these instructions are only advice and we cannot guarantee the results of your work or the safety of the installation. If you choose to modify a propeller using a drill bit, you do so completely at your own risk and RabidModels cannot assume any liability for the effectiveness or the correctness of the recommended procedure - your safety is completely your responsibility. Small propellers can break or fall off, and they can cause injury. Always wear eye protection while operating small electric motors. Do not operate a damaged prop – and enlarging the hole means it is damaged. Thank you for your understanding!